Fusible extension cord plug



May 26, 1953' A. G. BAUER 2,640,184

FUSIBLE EXTENSION CORD PLUG Original iled Nov. 8, 19 6 INVENTOR. )Z/Zdr 6390092: B 1

ATTO/P/Yfy Patented May 26, 1953 FUSIBLE EXTENSION GORD PLUG.

Arthur G. Bauer, Wantagh, N. Y., assignor, bymesne assignments, to Charles E. Eggers, Great Neck, N; Y.

Original-application November 8, 1946,.Serial No. 708,547. Divided and this application October 5, 1949, SerialNo. 119,735

1 Claim. 1

"his invention relates to improvements in a quick. detachable connecting plug for electric extension cords and the like. The invention is more particularly concerned-with an attachment plug oi novel construction and which is adapted for use with a fuse element whereby both legs of the extension cord circuit are protected against overload as well as short circuiting. The plug may be used with greater safety in connecting usual electric appliances, such as lamps, flat irons, toasters, and-the like tothe terminals-of outlet sockets and was firstshown and'described iniiny co pending application, Serial-No. 708,547, filed November 8, 1946, which has matured into Patent No. 2,486,380, and. of which thisapplication is division.

Anobject of the invention: is, therefore, the provisionv of an improved. electrical. connection plug having a recessed outer end into which may. be fitted a readily accessible andexchangeable fuse element which substantially fillstherecess and covers thewire terminals therein, whereby inthe event of an overload or. short circuit in the. plug circuit the fuse is caused tov burn and interrupt the circuit, thereby. preventing damage: to the, plug or appliances connected thereto.

Another object of the: invention is the provision of an improved. plug member; inwhich the circuit may be interrupted at the plug to thereby render appliances safev for handling; atany time desired, which are connected in the circuit withthe'plug.

A further object of the invention is the provision of an electricplug for use with acircuit controlling fuse mountable in the outer end thereof so that thefuse may be readily examined for removal or replacement only upon withdrawing of the plug from an associated line socket andthereby breaking the circuit through the plug without danger of burns or shock in so doing.

A still further object of the invention is the provision ofa one-piece plug having pairs of terminal contacts and cord binding connections disposed withina recessed chamber in the outer or prong end of the plug adapted for use with an'insulatedfuse containing member for bridging the contacts and being removably supported within the recessed chamber so as to provide a closure for the chamber and a protecting cover for the contacts and binding cord connections therein.

A still further object of the invention is the provision of an improved electrical plug com-- 2'- prising a body which is preferably constructed in one piece from any suitable insulating ma terial, such as rubber, the body having a relatively deep recess inone end thereof with opposed walls of the recess provided with translversely alinedslots opening through the ends of the walls, the plug also having a pair of spaced contacts at each of two opposite sides of the'recess with-one contact of eachpair being integral withasocket engaging prong projecting outwardly from the recess, and the recess being adapted to receive a circuit completing member. having end portions removablyreceivable in the slots for facilitating removal'of'tlie men iber'by engagement of the end portions by the. fingers.

Other objects and advantages of the inven tion will become apparent in the course of the following description, taken in connection with the accompanying drawings, whereinzl Fig. l is an end view 'of the improved plug as observed from the left of Fig. 2, the view being ona substantially enlarged scale;

Fig. 2 is a vertical sectional view as observed in the plane of line 22-, Fig-.1;

Fig. 3. is an endview. of the plug corresponding to Fig. 1, butshowing a fuse member in operative position withinthe recessed end thereof;

Figal'is an elevational view of the plug as viewedfrom' one side thereof; and' Fig; 5 is' an elevational view of the plug as viewed from another side thereof and being partly in section to show a fuse member in operative association: with a terminal contact within the recess in the plug.

All: of the viewssof the drawings as brieflydescribed above show. the structure of the plug about double actual size:

Referring nowxin detail to the drawings, P

designates the improved electric cord plug, which; asshowmembodiesa one-piece insulating body memberlfl providedwvitha relatively deep and substantially rectangular recess II in one end thereof. The body'isshownasfurther provided with a cord. receiving aperture l2. opening through: the opposite: end thereof and which aperture opens into. the; recess H;,through an elongatedirecess portion l 3: The body-is further providedwith-slots Ha inopposed walls thereof opening into recess Ii. While the body lll' may' be constructed of any suitable insulation material, it is preferably constructed of rubber which is readily molded to desired shape and unbreakable in the event of impact with hard objects.

This body I is also provided with a pair of socket engageable prongs I4 each of which is constructed from a strip of spring brass which is folded over in the provision of yieldable' terminal portions I5, for frictional fit within the socket member. The strip is further bent over in the provision of attaching portions I6, embedded in the body I 0. The prongs I4 each further includes a contact II, disposed laterally of the prong proper, as is clearly indicated in Fig. 1. The contacts I1 are preferably provided as offset continuations of the strips from which the prongs are formed.

As is indicated in Fig. 1, each contact I! is disposed to one side of its respective prong in diagonally opposed corners of the recess II. A contact I8 is disposed in each of the other diagonally opposed corners of the recess II adjacent but spaced from a prong I4 and these terminal contacts include base portions I 9, which are provided with tapped apertures 20, formed by extruding the metal from the base portions. The tapped apertures are adapted to receive the cord binding screws 2| whose shanks may extend into the recesses 22, in the body I0. The terminal contacts I8 further include doubled-over foot portions 23, anchored in the body.

As is more clearly indicated in Fig. 2, the prong contacts I! and terminal contacts I8, which are also preferably of spring brass, include similar rounded grooves 24 and 25 respectively for a purpose later to appear. Also as indicated in Fig. 1, the contacts I! and I8 are disposed in pairs adjacent the prongs I4 with the contacts of each pair disposed in alinement at opposite sides of the respective prong.

In the use of the plug P an electric cord is re movably entered into or molded in the plugthrough apertures I2I3 and the two wires of the cord may be individually clamped to the base portions I 9 of the terminal contacts I8, by means of the screws 2!. Instead of using the screw type binding post 2i it will be understood that any well known or approved terminal connections may be substituted, or the cord wires may be soldered directly to the terminal members I8, without altering the invention.

The construction of the plug, as described and shown in Fig. 1, is such that current cannot be conducted from the prongs I4 to the cord Wires through the terminal contacts I8, unless the contacts I1 and I8 adjacent each prong are placed in an electrical circuit. As shown this may be effected by a fuse member F, illustrated in operative association with the plug in Figs. 3, 4 and 5. This fuse member may embody a pair of superimposed mating shells 26 connected by side terminals 4i and having reduced end portions 26a, which may be formed of suitable relatively rigid transparent insulating material.

It is to be particularly noted that the fuse member F is insertable within and removable from the recess II by movement thereof axially of the plug, since the prongs I4 ride in the recesses 45 in the shells 25, and by reason of such mounting a fuse cannot be inspected or replaced until the plug is withdrawn from a wall or other line socket thereby avoiding any possible danger of burn and shock in examining or replacing the fuse member.

It is to be further noted that with the improved form of plug the fuse member when in position within the recessed end of the plug (see Fig. 3) provides an adequate cover for the binding screws 2| and associated cord ends. Since the reduced shell end portions 26a of the fuse seat in the slots Ila, in the assembled position of the fuse and plug members and project slightly beyond the adjacent wall portions (see Fig. 4), these ends of the fuse may be grasped by the fingers and the terminals 4| of the fuse member F easily withdrawn from their normal oper ative association with the contacts I! and I8. With the fuse removed the plug and appliance cord connecting the binding screws therein is rendered inoperative even if reinserted into the wall socket. Hence, the reinserted plug element, as shown in Figs. 1 and 2 without the fuse therein, provides a further safety means against tampering by children etc.

While I have herein disclosed my invention in a preferred form, it is obvious that changes in structure may be resorted to without departing from the spirit of the invention, and I therefore do not desire to be limited to the precise form disclosed beyond the limitations imposed by the following claim.

What I claim and desire to secure by U. S. Letters Patent is:

An attachment plug comprising a one-piece body member having a substantially rectangular and relatively deep recess in one end thereof for the removable reception of a circuit completing generally rectangular closure member having laterally projecting finger engageable extensions, a cord receiving aperture extending through the opposite end of the body member and communicating with said recess centrally thereof, a pair of terminal contacts supported by the body member at the base of said recess at opposite sides of said aperture and each provided with a binding screw, a pair of socket engageable prongs supported by the body member and each provided with a contact in spaced and laterally aligned relation to one of said terminal contacts, one of each of said first contacts and second contacts being disposed adjacent one wall of the recess at opposite sides of one prong, the other of said first and second contacts being disposed adjacent the opposite wall of the recess at opposite sides of the other prong, and said body member being provided with a relatively deep slot in each of the other opposite walls of the recess and opening through the upper edges thereof for receiving said finger engageable extensions.

ARTHUR G. BAUER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,863,824 Barnett June 21, 1932 2,176,793 Fry Oct. 17, 1939 2,217,585 Yates Oct. 8, 1940 2,396,901 Tiffany Mar. 19, 1946 2,448,389 Williams Aug. 31, 1948 2,486,380 Bauer Nov. 1, 1949 

